Fails if the function fails when applied to the list of ASSUMEd assumptions,
or if the resulting tactic fails when applied to the goal.

COMMENTS

There is nothing magical about ASSUM_LIST: the same effect can usually be
achieved just as conveniently by using ASSUME a wherever the
assumption a is needed. If ASSUM_LIST is used, it is extremely unwise to
use a function which selects elements from its argument list by number, since
the ordering of assumptions should not be relied on.